This invention relates generally to the field of parking brake cable systems, and in particular, to electric park brake cable systems having a mechanical release.
Electric, or electro-mechanically actuated, devices are known in the art for providing a parking brake function for motor vehicles. Such systems typically use a motor and associated gear assembly that are connected to a cable, which is in turn connected to the vehicle""s braking system. Upon actuation of the motor, tension is applied to the cable, engaging the vehicle""s brakes. A problem with such systems occurs when the electric parking brake cannot be disengaged, e.g., due to loss of electrical power, preventing release of the parking brake.
U.S. Pat. No. 6,244,394 to Gutierrez et al. discloses an electric parking brake system having a motor driven telescopic device for application of the parking brake. A release device including a pawl and mating socket in a stud is integrated in the telescopic device, and serves to release the parking brake in the event that the electric parking brake cannot be disengaged.
It is an object of the present invention to provide a mechanical release for an electric parking brake system that reduces or wholly overcomes some or all of the difficulties inherent in prior known devices. Particular objects and advantages of the invention will be apparent to those skilled in the art, that is, those who are knowledgeable or experienced in this field of technology, in view of the following disclosure of the invention and detailed description of preferred embodiments.
The principles of the invention may be used to advantage to provide a simple and efficient mechanical release for an electric parking brake.
In accordance with a first embodiment, a mechanical release for an electric parking brake system includes a housing. One end of a first brake cable engages the housing. A lever is pivotally connected at a first end thereof to the housing. A second brake cable is pivotally connected at one end thereof to a second end of the lever. A locking member engages the lever to releasably secure the lever to the housing.
In accordance with a second embodiment, a device for releasing an electric parking brake system includes a housing member adapted to be connected to a first brake cable. A lever is pivotally connected at a first end to the housing member and is adapted to be connected at a second end to a second brake cable. A locking member engages the lever to releasably secure the lever to the housing member.
In accordance with yet another embodiment, a mechanical release for an electric parking brake system includes a housing having a first wall and an opposed second wall. A first brake cable has a fitting at one end thereof, and the fitting engages the housing. A lever has a first arm and a second arm, and the lever is positioned between the first and second walls of the housing. A pivot pin extends through the first arm and the second arm of the lever, and through the first and second walls of the housing. A second brake cable has a fitting at one end thereof that is pivotally connected to the lever. A locking pin engages the lever to releasably secure the lever to the housing. A coil spring biases the locking pin into engagement with the lever, and a pull cable is secured to the locking pin.
From the foregoing disclosure, it will be readily apparent to those skilled in the art, that is, those who are knowledgeable or experienced in this area of technology, that the present invention provides a significant advance. Preferred embodiments of the mechanical release mechanism of the present invention can provide an efficient and cost-effective manner of providing for the release of an electric parking brake system in the event the electric braking system cannot be disengaged. These and additional features and advantages of the invention disclosed here will be further understood from the following detailed disclosure of preferred embodiments.